The installation of a faucet onto a countertop or sink is a difficult and time-consuming task. At least some of the installation must be done with the installer being in the confined and hard to work in area under the counter or sink. There is a need to provide a less cumbersome and complicated system of installing faucets or interchanging different faucet styles, such as single handle faucets and two handle faucets, onto a countertop or sink which can be done largely from the top of the countertop or sink. The present invention provides such a system.